This project to understand the complex and evolving role of microbes on coral reefs, is a largescale, multi-year field experiment that examines links between microorganisms, macroorganisms, and abiotic factors. Using a fully‐crossed, factorial experimental design, we mimic overfishing (via fish exclosures) and eutrophication (via repeated nutrient additions) on a coral reef in order to decipher the proximate mechanisms that alter coral microbial communities (e.g., seasonality vs. increased nutrient availability vs.increased algal abundance) and potentially lead to habitat degradation. Despite the call for more research on the roles that microbes play in maintaining coral health and productivity, we know little about how changes to macroalgal and fish communities impact the diversity and abundance of microbes on corals or how shifts in the microbial community translate into changes in disease prevalence and severity. Therefore we are empirically examining how alterations to nutrient availability and herbivore abundance affect both the structure and function of the reef-associated microbial community (bacteria, single celled eukaryotes, and viruses on corals and algae) and the macro-community (algae and corals) over various temporal (days to years) and spatial scales (millimeters to meters). This extensive time-series represents a foundational dataset for understanding environmentally-mediated changes in the structure and function of coral reef microbial communities and, importantly, how those changes feed back to ecosystem health over ecologically relevant time scales. This experiment is named Project HERBIVORE (Habitat Enrichment and Removal; Bacteria, Invertebrates, & Viruses On Reef Ecosystems).
|
